saturation zone

saturation zone
layers of saturation zone

1. Sa t ur a t e d zone is c l a ss i fied into 4 ca t egor i es. Aquifer Aquitard Aquic l ude Aquifuge

2. A Q U I FER An aquifer is a layer of porous substrate that contains and transmits groundwater. An aquifer is an underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) from which groundwater can be extracted using a water well. Aquifers may occur at various depths.

3. T Y P ES O F A Q U I FER UNCONFINED AQUIFER: Unconfined aquifers are sometimes also called water table or phreatic aquifers, because their upper boundary is the water table When water can flow directly between the surface and the saturated zone of an aquifer, the aquifer is unconfined. The deeper parts of unconfined aquifers are usually more saturated since gravity causes water to flow downward.

4. CONFINED AQUIFER: A water-bearing subsurface stratum that is bounded above and below by formations of impermeable, or relatively impermeable soil or rock. Also know as an artesian aquifer.

5. P R OP E RTIES O F T H E A Q UI F ER Poros i ty Specific yield Specific retent i on Storage by e f ficiency ( f ield capacity) Per m eab i l i ty .

6. POROSITY: Porosity or void fraction is a measure of the void (i.e., "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0–1, or as a percentage between 0–100%. Porosity of surface soil typically decreases as particle size increases.

7. S P E CI F I C YI E L D The quantity of water which a unit volume of aquifer, after being saturated, will yield by gravity; it is expressed either as a ratio or as a percentage of the volume of the aquifer; specific yield is a measure of the water available to wells.

8. SPE C IFI C R E T N TI O N: The ratio of the volume of water that a given body of rock or soil will hold against the pull of gravity to the volume of the body itself. It is usually expressed as a percentage FIELD C A P AC I T Y: Field capacity is the amount of soil moisture or water content held in soil after excess water has drained away . The physical definition of field capacity is the bulk water content retained in soil

9. P E RM EA B IL I T Y The ability of water to flow through a soil is referred to as the soil's permeability.

10. AQUICLUDE It is a solid, impermeable area underlying or overlying an aquifer. If the impermeable area overlies the aquifer pressure could cause it to become a confined aquifer. A solid, impermeable area underlying or overlying an aquifer. It can absorb water but cannot transmit it in significant amount.

11. AQ U IFUGE: An impermeable body of rock which contains no interconnected openings or interstices and therefore neither absorbs nor transmits water. AQUITARD: A bed of low permeability adjacent to an aquifer; may serve as a storage unit for groundwater, although it does not yield water readily.